一.集合操作命令

SADD key member1 [member2]:
sadd set1 a b c d

sadd set1 a

0表示没有添加成功,因为集合中已经有了这个元素了,因此无法重复添加。
SMEMBERS key:
smembers set1
SCARD key:
scard set1

SADD key member1 [member2]:
sadd key a b x y

SINTER key1 [key2]
SINTER set1 set2



SUNION key1 [key2]
SUNION set1 set2

SREM key member1 [member2]
srem set1 a

